A renewed appeal is being issued by police probing fraudulent phone calls being made to vulnerable old folk in Dacorum.

And they are stressing that people should never part with their bank details or cash if they receive a phone call from someone claiming to be a police officer investigating a fraud.

They have launched Operation Policy to investigate the fraudulent phone calls, and say the fraudsters are now changing their tactics and trying to persuade victims to withdraw large sums of cash.

A Tring woman in her 80s was called by a man claiming to be a police officer yesterday, Thursday.

He told that he had arrested someone trying to take money from her account and then encouraged her to withdraw a large amount of cash from her bank which would then be picked up by a courier.

The woman tried to withdraw money from her account in a local branch but the bank became suspicious that the woman may have been conned and contacted police.

A similar call was made to a Hemel Hempstead woman on Wednesday

She was told a similar story by the caller, who advised her to put the phone down and verify the report by calling the police fraud department via 101.

The woman did so, but did not realise that the caller has not ended the call and remained on the line.

The woman later called police via 101 on her mobile and it was then discovered she had been scammed. No money was withdrawn.

Dacorum’s Chief Insp Glen Channer said: “Clearly the offenders are changing the way they operate.

“It is vitally important that people are aware that this type of crime is happening in Dacorum. In other areas of the county, victims have had thousands of pounds stolen in this way.

“The advice is very clear – police officers would NEVER ask you to reveal your personal bank account details, including your PIN or bank card and they would never ask someone to withdraw money.

“If you do get a call, use a mobile phone if you have one to call police or leave the landline for at least five minutes before attempting to make an outside call. You can always test the line first by phoning a friend or relative.”